Nearly all of our laws discriminate. The laws against robbery discriminate against those who take the property of others by force or the threat thereof. Our gun control laws discriminate against convicted felons, against minors, against U.S. citizens that have given up their citizenshp. School attendance laws discriminate against (or you might argue, in favor of) minors. They discriminate based on geography--you can't send your kid to a certain school unless you live in that district. Our laws discriminate based on age as to what public offices you may hold. Our laws discriminate against people who drive with more than a certain amount of alcohol in their blood--even if they haven't hit anyone yet!

The entire basis of law is discrimination based on criteria established legislative bodies and in some cases, by federal and state constitutions. The only reason that "discrimination" became a dirty word is because discrimination based on race was determined by a strong majority of those who decided to stay in the Union as wrong.

Now, you certainly regard discrimination based on sexual orientation as wrong. I would certainly agree that in many situations, it is wrong, and with a few exceptions, I don't regard such discrimination as particularly sensible. But equal protection of the law means quite a bit less than you think.

I pointed out that the evidence is quite clear that the primary focus of the 14th Amendment, as demonstrated by statements from both proponents and opponents, was protecting the rights of blacks, and secondarily, the rights of Unionist whites who either already lived in the South, or had moved there after the Civil War. (Amusingly enough, I have seen liberals defend the racism of affirmative action on the grounds that the 14th Amendment was intended to protect blacks--not whites. There's some merit to such an historical analysis, as offensive as the results might turn out to be.)

So, one of the liberals commenting over there decided to show his superiority over me by asking if the 14th Amendment prohibited discrimination based on gender. The answer is very clearly, "No." If it had, there would have been no need for the later amendment to the Constitution granting women the right to vote, and all this discussion of an Equal Rights Amendment a couple of decades back would have been completely pointless.

It is not that no one thought of this argument. There was a challenge in 1872 to Missouri's law limiting the vote to men that ended up before the Supreme Court in Minor v. Happersett, 88 U.S. 162 (1874). This was specifically raised on the "privileges and immunities" clause of the 14th Amendment, so it isn't strictly an equal protection argument, but the Court's position on this is essentially an original intent argument based on the fact that Congress passed the 15th Amendment to guarantee the right of male citizens to vote--something that suggests that the right to vote was not one of the "privileges and immunities" that the 14th Amendment protected. A similar argument, and a similar response, shows up in Bradwell v. Illinois, 83 U.S. 130 (1872), where a woman challenged an Illinois law that only licensed men to be lawyers.

As late as Goesaert v. Cleary, 335 U.S. 464 (1948), the Supreme Court upheld a Michigan law that prohibited woman from being licensed as bartenders unless they were the wife or daughter of the owner, and decided that this was no violation of equal protection:

The Constitution in enjoining the equal protection of the laws upon States precludes irrational discrimination as between persons or groups of persons in the incidence of a law. But the Constitution does not require situations 'which are different in fact or opinion to be treated in law as though they were the same.' Tigner v. State of Texas, 310 U.S. 141, 147 , 882, 130 A.L.R. 1321.

In short, as long as the statute's distinctions between different women in different situations had some connection to a perceived public need, there was no violation of equal protection--and certainly, the mere fact that the law discriminated against women as a sex was not an equal protection violation.